Timely paper! Rice agriculture must have been brought to India by the Austro-Asiatics. But the the EDAR genes that the Austro-Asiatics also brought with them do not seem to have been selected in India unlike in East Asia. The Munda only have 5% East Asian EDAR while having 15 to 30% East Asian ancestry.

Why did the East Asian variant lose its selective advantage in India? The reason must be that EDAR selection in East Asia was by sexual selection. Darwin proposed this to be the reason for non-adaptive differences between the races. Sexual selection, especially for cosmetic factors, is mostly a matter of female choice – while men may prefer blondes they will readily settle for brunettes but women hold out for Mr. Right. The Austro-Asiatics spread in India by their men marrying local women. These women did not care one way or the other for the thick straight hair of the Austro-Asiatic men but chose them for their agricultural skills! Thus the East Asian EDAR gene got diluted to a low level.

Is the calculated EDAR frequency of Munda too low compared to their calculated Mongoloid admixture? It doesn’t seem to me that way.

Dwight E. Howell

The ag expansion was almost certainly in part a military expansion. Such expansion is usually made by young males and they often grab onto and/or at the least have sex with the most attractive local females.

On the other hand guys are rarely able to jump from shrinking groups to growing groups worth a flip.

http://blogs.discovermagazine.com/gnxp Razib Khan

Is the calculated EDAR frequency of Munda too low compared to their calculated Mongoloid admixture? It doesn’t seem to me that way.

i agree with you. i posted the comment as a joke. it was kind of funny.

Mary

I wouldn’t want to the object of that withering glare.

Onur

i agree with you. i posted the comment as a joke. it was kind of funny.

The EDAR allele (rs3827760) is exclusive to Mongoloids (including Amerindians), most of Mongoloid individuals possess it, but still there are a great many Mongoloid individuals who lack it, and there is significant variation in the EDAR ratio of Mongoloid and semi-Mongoloid peoples:

So the EDAR allele/Mongoloid ancestry ratio of Munda isn’t unusual, especially given the peripheral location (for Mongoloids) of the ancestral homeland of their Mongoloid ancestors. Uighurs, Hazaras and Uzbeks have more Mongoloid ancestry than Munda but despite that they lack the EDAR allele, so their situation is much more unusual than that of Munda.

Onur

Apparently, in addition to the previous SNP (rs3827760), there is another SNP of EDAR (rs11123719) and the EDAR allele of this one exists all over the world, but in significant amounts only in Mongoloids and partially in Australoids:

Note that in the frequency of the EDAR allele of this SNP Uighurs and Hazaras are midway between Caucasoids and Mongoloids, this time in accordance with their Mongoloid ancestry ratios. Unfortunately, as this is an HGDP map, there is no Uzbek sample (they also don’t exist on the previous map, but at least on that map their EDAR allele frequency can easily be inferred from those of Uighurs and Hazaras and other nearby populations).

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About Razib Khan

I have degrees in biology and biochemistry, a passion for genetics, history, and philosophy, and shrimp is my favorite food. In relation to nationality I'm a American Northwesterner, in politics I'm a reactionary, and as for religion I have none (I'm an atheist). If you want to know more, see the links at http://www.razib.com